Sustainable development of human society requires the net zero carbon emission, the world’s urgent mission to accomplish by 2050. It is foreseen that clean energy production, storage and utilization will soon replace those relying on oil and coal. To accelerate this transition towards carbon neutrality, the research in my group is focused on the renewable energy storage and conversion systems, particularly using electrochemical methods. In this talk, I will first show our efforts in the design of novel electrochemical energy storage systems for the grid and transportation applications. Fast-charging (~18 seconds), durable (more than 6000 cycles) and cost-effective aqueous sodium-ion batteries are demonstrated in our lab and further improved to compete with the state-of-the-arts. Then I will illustrate our research results on green hydrogen production through water-splitting using electrochemical energy conversion devices. Highly efficient electrocatalysts (~1000 times better in activity than commercial standards) are developed to facilitate the sluggish reactions. Besides presenting our understanding of electrochemical processes at the molecular level in these energy systems using advanced synchrotron X-ray spectroscopy and scattering characterizations, I will also show examples of how we collaborate with companies for possible commercialization of our research products.